It is World War II and Major Jonathan Smith (Richard Burton) is heading out to Bavaria in an aeroplane, leading a group of British troops and one American, Lieutenant Schaffer (Clint Eastwood), on a top secret mission into enemy territory. They must rescue an American officer who has knowledge of all the plans to the Allies' invasion of Europe, and understandably it is imperative that he should be returned before the Nazis manage to get any revealing information out of him. They cannot simply blow up the remote mountain castle he is being held in as the Americans wouldn't like it, so off Smith and his colleagues go - but what if there is a traitor in their midst?

If the phrase "Broadsword calling Danny Boy" means anything to you, then you're undoubtedly a fan of this tale of derring do from the pen of prolific thriller writer Alistair MacLean, perhaps the finest film made from his work; some would say it was even better than The Guns of Navarone, the other contender for the best MacLean adaptation crown. That said, at the height of his decades-long popularity for a while it seemed as if you couldn't visit the cinema without bumping into one of these versions of his novels, but now the success has died down to an extent, how does Where Eagles Dare stand up?

Very well indeed, as it shows off the writer's skill with a great story, probably because he wrote the script and the production stuck faithfully to his twists and turns - and what twists there are! In no way a chick flick despite the presence of a female agent, Mary (Mary Ure), this is the kind of escapist material that boys of all ages, from seven to seventy and beyond, can appreciate. Part of the fun is spotting how implausible the plot is, from the obvious stunt doubles handling the trickier physical situations - Eastwood mocked the film as "Where Stuntmen Dare" in an exhibition of how little participation he felt he had to do on it - to a series of double crosses building into the rarely attempted triple crosses that would beggar belief in any other context.

Yet these filmmakers allow you throw your cares from your shoulders for two and a half hours and simply go with it all, and there is something irresistible about its commitment to adventure. Yes, Burton was well into his drink-sozzled phase by this time, and you can spot his hands trembling if you look hard enough, so it's hard to believe he could pull off the feats he does if you're truly honest with yourself (leaping from cable car to cable car? In his state?!), but you're with him all the way, as if he can have faith in this material then we can too. Eastwood is in far better shape, and as noted if he does appear to be playing second fiddle to Burton for much of this, he does grab every sardonic line or bit of action to make sure his presence is felt.

The film is exceedingly well-cast throughout, with the soldiers Smith is unsure of leaving us wondering who could be the traitor (and what an answer there is to that), to smaller roles such as the villains playing it suitably hissable. Derren Nesbitt especially makes the most of his Gestapo officer, and if his sly, grinning menace is rather thrown away by the end of his appearance, he leaves the impression of danger that is much needed and very welcome in an excursion such as this. By the end, the film is turned into an orgy of destruction as the small band of plucky Allies prove themselves far more ruthlessly efficient than the reputations of the Nazis, and are blowing up the bad guys with a seemingly never-ending supply of explosives - they must have slaughtered about a hundred people with nary a care in the world for morality. It might not have won any awards, but when Where Eagles Dare turns up on television for the umpteenth time, you'll know you're going to be entertained. Music by Ron Goodwin.